A satellite radio-controlled watch that receives a satellite radio wave containing time information and position information to correct time, and further automatically determines a time zone, based on the position information obtained from the satellite radio wave has been put into practice. Automatic determination of a time zone requires determination of a time zone to which the current position belongs.
Patent Literature 1 mentioned below discloses an electronic device that receives a satellite radio wave sent from a position information satellite to obtain position information and time information, in which only one time difference data is assigned to each of the segments having the same size, block data that is a collection of a predetermined number of segments is stored without overlap, and time difference data on a segment corresponding to the position information is obtained in the block data.